Study On Medium And Long Term Runoff Forecasting And Implicit Stochastic Optimal Operation Model For Ertan Hydropower Station

As an important non-engineering measure, forecast and control operation of reservoirs play an important role on guaranteeing safety of flood prevention,increasing efficiency of flood resources utilization and exerting comprehensive benefits of reservoirs. With the development of the technology of computer and the theory of optimization and forecasting, researchers of hydraulic engineering have utilized many different algorithms to solve the problems of hydrological forecasting and optimal operation of reservoirs system. A large amount of results have been made and come into effect. However, there are still a lot of problems by using these new methods duo to lack of reorganization of the mechanics of hydrological forecasting. Therefore, large numbers of subjects in basic work, theory study and improvement of models should be studied and solved further. This dissertation focuses on Ertan hydropower station of Yalong River basin downstream reach. On the premise of analysis the characteristics of the inflow runoff and operation, focusing on Medium and Long Term Runoff Forecasting and Implicit Stochastic Optimal Operation Model for Ertan hydropower station, the contents and results of this paper are listed, as follows.(1) Analysis of the characteristics of inflow runoff of Ertan Hydropower Station, including the change law of annual runoff, monthly runoff, flood season, non-flood season and so on, and deeply understand the inherent law of runoff variation, the results provide reference for medium and long term runoff forecasting; At the same time, regulating calculation of reservoir in series of annual runoff data measured of 48 years from 1958 to 2006 is performed, statistics analysis of operation characteristics of flow, reservoir water level, water head and output for mang years, the results provide important reference for forcasting the variation process of runoff, and provide scientific basis for scientific management and optimal operation of Ertan hydropower station.(2) This paper aims at the characteristics of the real runoff, sets up monthly runoff, division of the flood season and annual runoff forcast models respectively. Through forcasting research of the inflow into Ertan hydropower station from 1958 to 2006, the results show that monthly runoff, non-flood season and annual runoff reach a good precision, the qualification rates are all above 80%, which would be applied in practical operation. Meanwhile, because of inflow of flood season deeply influenced by rainfall, it is difficult to set up model only depending on runoff date, so this paper usesâ… ,â…¡,â…¢stage forecast which makes the results can be used. (3) Implicit Stochastic Optimal Operation Model is set up by taking Implicit Stochastic Optimal Operation method, on the basis of forecast and operation rules, by the way of regression analysis, researched optimal operation functions, including whether runoff forcast and division of operation functions of flood reason should be considerd, to show clearly the different runoff characteristics and operation mode of reservoir in flood reason and in non-flood reason lead to different operation functions. In the end, on the basic of intensive analysis, the procurability of regression factor in practical application, according to optimal operation functions, drawed reservoir optimal operation chart and established practical rules of reservoir optimal operation functions, in order to provide a giding in long-term operation of Ertan hydropower station.